Chair frame



FIG. 1 is a perspective view of a chair frame showing my new design;

FIG. 2 is a left side elevation view, the right side being a mirror image thereof;

FIG. 3 is a front elevational view;

FIG. 4 is a bottom plan view;

FIG. 5 is a top plan view;

FIG. 6 is a rear elevational view thereof; and,

FIG. 7 is a perspective view thereof showing a cushion carried by the chair frame.

The dashed lines in FIG. 7 are not a feature of the claimed design. 

The ornamental design for a chair frame, as shown. 